Corrosion and abrasion resistant sump pump for slurries



1 J. w. THOMPSON ETAL ,7

CORROSION AND ABRASION RESISTANT SUMP PUMP FOR SLURRIES Filed Aug. 31,1953 2 Sheets-Sheet 1 Snnentors; JOHN- W.- THOMPSON,-

ROBERT A. WILSON, ROBERT B. HOLLAND,

Oct. 8, 1957 J. w. THOMPSON EFAL 2,808,782

CORROSION AND ABRASION RESISTANT SUMP PUMP FOR SLURRIES Filed Aug. 51,1953 2 Sheets-Sheet 2 Z'mveutorg; JOHN W. THOMPSON, ROBERT A. WILSON,ROBERT B. HOLLAND,

nited States PatentOf CORROSION A ND ABRASION RESISTANTSUMP PUMP FORSLURRIES John W. Thompson, Robert A. Wilson, and Robert B. Holland, SaltLake City, Utah, assignors to The Galigher Company, Salt Lake City,Utah, acorporatlou of Utah Application August 31, 1953, Serial No.377,506

2 Claims. (Cl. 103-87) This invention relates to that class of pumpscommonly referred to as sump pumps, and is concerned particularly withsump pumps constructed to handle corrosive and abrasive liquids andslurries.

Practically all sump pumps commercially available are constructed in amanner making extremely difiicult, if not entirely impossible, anyeffective lining of the working parts with corrosion and abrasionresistant material, such as rubber. Furthermore, such pumps merely.produce a sucking action in the sump, which is ineffective to maintainthe material to be pumped in a state of agitation sufiicient to keepsolids in suspension during the pumping operation.

Thus, heretofore, there has been no sump pump capable of satisfactorygeneral industrial use in connection with the pumping of corrosive orabrasive liquids, particularly semi-liquid slurries.

This invention has, then, as one of its principal objects, the provisionof a sump pump which may be economically and effectively lined withrubber or other abrasion-resistant material, without interfering withpump action, and, as another important object, the provision of a sumppump which will accomplish a continuous and effective agitation of thematerial within the sump at the same time that it carries out itsprimary pumping function.

Another significant object is to eliminate dead areas within theimpeller casing of a sump pump, so that there can be no collection ofabrasive materials, to the detriment of the impeller from a wearstandpoint.

Furthermore, it is an object to accomplish the above without limitingthe extent to which any sump may be drained of material containedthereby, and, intact, with the possibility of removing liquid to even alower level than is customary, without risk of air-lock.

Another important feature in the accomplishment of the above objects isthe fact that the impeller shaft depends, free and clear of otherstructure, from a bearing suspension in supporting structure adapted tobe positioned above the level of liquidin the sump, and that such shaftenters the impeller, casing through and intermediate of an upper openingtherein which is sufficiently large .to serve as a suction inlet for thepump. Thus, there is sufficient space between the impeller casing andthe impeller shaft to permit the, application of an adequate covering ofabrasive-resistant material tothe otherwise exposed metal parts normallysubmerged in the liquid to be pumped.

Lining of the pump parts with an abrasive-resistant covering is madeeasier, moreover, by the fact that, in preferred constructions, theinterior walls of the impeller casing are concentric with the impeller.

.Another highly important feature resides in the provision ofcorresponding suction inlet openings in both the upper and lowerwallsofthe impeller casing, whereby eifective suction and inflow ofmaterial is accomplished at both the top and thebottomsof .thezimpellercasing,

2,808,782 Patented Oct. 8, 1957 which, in conjunction with the impellermounting, is effective to produce the desired agitating action in thebody of material to be pumped.

In order to provide against air lock as the level of liquid in the sumpreaches the impeller casing, the impeller is divided into an upper and alower part by an imperforate, horizontal septum. Thus, there isprovided, in effect, both upper and lower pumping mechanisms, which arecorrelated, respectively, with the upper and lower suction inletopenings. When the liquid in the sump drops below the upper inletopening, the lower pumping mechanism continues to withdraw the liquidfrom the sump until the level of liquid reaches the level of the lowerintake opening.

Because of the free suspension of the elongate impeller shaft, withoutbearing or other support along its length, the impeller shaft rotates incontact with the liquid to be pumped, thereby imparting a swirlingmotion to the liquid in the sump, which adds to the agitation effect ofthe double inlet arrangement of the impeller casing. The result is acontinuous vigorous agitation of the material in the sump, exteriorly ofthe impeller casing, which agitation is elfective to maintain solids insuspension in those instances where a metallurgical slurry or the likeis the material to be pumped.

This action is further enhanced by the fact that, suspended as it isfrom an upper support, without bearings at its lower end, the elongateimpeller shaft executes a limited sideward whipping motion as it gets upto speed, dynamic balance being achieved when operating speeds arereached.

By supporting the pump casing from the impeller shaft supportingstructure by means of a plurality of mutually spaced, depending legspositioned circumferentially of the impeller casing, one or more of suchlegs may be a pipe communicating with the interior of the impellercasing and serving as a discharge conduit for the pump.

Preferred details of construction and further objects and features ofthe invention will be dealt with in the following description of thepreferred specific embodiment illustrated in the accompanying drawings.

In the drawings:

Fig. 1 represents a side elevation, partly in vertical section takenalong the line 1-1 of Fig. 3;

Fig. 2, a top plan partly in horizontal section taken along the line 2-2of Fig. 1;

Fig. 3, a horizontal section taken along the line 3-3 of Fig. '1;

Fig. 4, a similar section taken along the line 4-4 of Fig. 1;

Fig. 5, a view in perspective of the pump of Fig. l, drawnto a reducedscale and partly diagrammatic in character, illustrating a typical flowpattern of liquid in the sump during operation of the pump;

Fig. 6, a perspective detail view, looking from the bottom, of the formof impeller illustrated in Figs. 1 and 6; and

Fig. 7, a similar view of a somewhat different form of impeller.

Referring-to the drawings:

,In the particular embodiment illustrated, the pumpis arrangedforeitherdirect support on the bottom of the sump, or for suspension from a sumpcover. For the latter purpose, a horizontal supporting plate 10 isprovided, with openings 11 for use in bolting or otherwise securing thepump .to the sump cover.

The plate 10 serves as a suspension mounting for an elongate impellershaft '12, which depends vertically therefrom for rotation free andclear of other structure. A bearing 13 rigidly secured to the-plate 10,as by means of bolts 14, journals the shaft 12. for rotation, andprovides an intermediate support therefor in its extension fromattachment, at 15, Fig. l, to the drive shaft of the customary electricmotor 16. Between the motors 16 and the supporting plate 10, the shaft12 is protected by an elongate housing17 anchored to the plate by meansof a base plate 17a.

At the lower end of the impeller shaft 12 is rigidly affixed athorizontally disposed, disk impeller 18. An impeller casing 19 surroundssuch impeller, and is mounted in fixed relation thereto by means of aplurality of, in this instance three, legs 20, 21, and 22, seeespecially Fig. 3, which depend from fixed securement, as by means ofwelding, to the underside of supporting plate 10.

While any or all of these legs may communicate with the interior ofimpeller casing 19, and thereby serve as pressure discharge conduits forthe pump, in the present instance only the leg 20 is here shown as sodoing. For this purpose, it possesses a somewhat larger diameter thanthe legs 21 and 22, and extends through and upwardly of the plate 10 toa termination 20a adapted to receive such additional discharge piping asmay be required by any given installation.

The impeller casing 19 is dimensioned internally to provide ample leewayfor the rubber or other corrosion and abrasion-resistant coveringindicated in the drawing as being applied to all submerged metalsurfaces which are normally exposed to the material being pumped, and isprovided with both an upper suction inlet opening 25 and a lower suctioninlet opening 26, the two openings being preferably concentric and ofcorresponding size. As illustrated, such openings possess diametersconsiderably in excess of the diameter of the impeller shaft 12, so thatsuch impeller shaft is amply spaced from the defining margins of theupper recess 25, to afford effective entry of the to-be-pumped materialto the interior of the impeller casing and to provide leeway for limitedwhipping action of such shaft as it comes up to or drops down fromoperating speed following the turning on or turning off of the pump.

As will be seen in Fig. 4, the interior ot fhe pump casing 19 ispreferably circular and concentric with the circular impeller 18 andimpeller shaft 12. This makes for economy and convenience in the liningof the casing with rubber, and contributes to the achievement of dynamicbalance by the impeller in its rotation within the casing in thoseinstances, such as that illustrated, where symmetrical discharge portsare not provided.

It will be noted that, in the operation of the pump, see Fig. 5,material from the sump will be drawn into the pump simultaneously fromboth above and below the impeller casing; furthermore, that the freelysuspended impeller shaft 12 is open to and in contact with, along itsentire length, the material to be pumped from the sump. This promotes ahighly advantageous agitation and circulation of the material to bepumped, which results in solid particles being maintained in liquidsuspension during operation of the pump, and, consequently, a minimum ofsands collected on the bottom of the sump.

As indicated in Fig. 5, and particularly by the arrows appended thereto,a definite swirling of the liquid to be pumped is produced both aboveand below the impeller casing by reason of the upper and lower suctioninlet openings thereof. Furthermore, a vertical motion is imparted tothe body of liquid surrounding the impeller shaft, whereby effectivefolding over of the slime-carrying or other semi-liquid material to bepumped is effected, together with a feeding of such material into theupper discharge opening longitudinally along the impeller shaft.

It should be particularly noted that, constructed as it is, there are nodead areas within the impeller casing, as are usual with conventionalsump pumps, and that the double suction feature provides for anefiective, dynamic sweeping of all parts of the impeller casing byflowing liquid during operation. 3

It is a feature of the invention that the impeller be formed with animperforate horizontal septum or dividing wall 18a intermediate thevertical extension of the several pump vanes, 18b, so as to, in effect,provide upper and lower pumping portions, both being provided withcorresponding vanes 18b. Thus, when the level of liquid in the sumpreaches the upper suction inlet 25, the pump will continue to function,without air lock, by reason of the continued submergence of the lowerportion of the impeller. In this manner, the desirable agitating featureof the pump is had without sacrifice of pumping effectivcness down tothe level of the lower suction intake opening 26, or of any extensionthereof which may be provided.

Suitable screens or grids may be provided about the suction inletopenings, for example, as illustrated at 27 and 28, respectively, Fig.1;

The vanes of the impeller may be of various formations. Thus, instead ofbeing rectilinear and radial, as in the impeller 18, see especially Fig.6, they may be of the arcuate formation and placed as in the impeller 30of Fig. 7, where 30a indicates the imperforate septum and 30b indicatesthe various vanes.

Whereas, this invention is here illustrated with respect to a particularpreferred construction, it should be understood that various changes maybe made therein without departing from the scope of the claims whichhere follow.

We claim:

1. A corrosion and abrasion resistant sump pump, comprising ahorizontally extending support; an elongate impeller shaft; bearingmeans mounting an upper portion of said shaft in the support, so thatthe lower por tion thereof depends vertically from said support free andclear of other structure, said lower portion being rubber covered; arubber covered, horizontally disposed, circular impeller secured to thelower end of said shaft; a rubber lined casing surrounding said impellerand defining a corrosion and abrasion resistant impeller chamber ofright cylindrical formation concentric with and of effectively greaterdiameter than the impeller; mutually spaced legs depending from fixedsecurement to said support and secured at their lower ends to saidimpeller casing for supporting the latter in fixed concentricrelationship with said impeller, one of said legs constituting adischarge pipe leading directly vertically from communication with theinterior of said casing at the outer periphery thereof and extendingthrough said support to a discharge termination above the supportadapted for connection to a discharge line; said casing having a pair ofinlet openings formed in mutually opposing relationship centrally of theupper and lower casing walls, respectively, above and below saidimpeller, said impeller shaft passing through and being spaced apartfrom the defining margins of the upper of said inlet openings and theimpeller being wholly contained within and spaced apart from said casingso that impeller and impeller shaft are free to whip as the pumpcommences operation; and means in engagement with said impeller shaftabove said support for rotating said impeller shaft.

2. The corrosion and abrasion resistant sump pump of claim 1, whereinprotective grids are secured to the impeller casing externally thereofand in surrounding relationship to the upper and lower inlet openingsthereto, respectively, the upper grid surrounding the impeller shaft inspaced relationship therewith.

References Cited in the file of this patent UNITED STATES PATENTS1,381,673 Sherwood June 14, 1921 2,143,032 Ruthman Ian. 10, 19392,179,730 Ruthman Nov. 14, 1939 2,207,183 Thrush July 9, 1940 2,207,208Thrush July 9, 1940 (Other references on following page) 5 UNITED STATESPATENTS Thrush Oct. 7, 1941 Duden Apr. 8, 1942 Nagle Nov. 3, 1942Lamphere Feb. 27, 1951 Ha entjens Jan. 13, 1953 6 Wahle Nov. 17, 1953Kreitchman Mar. 9, 1954 Staaf Apr. 19, 1955 FOREIGN PATENTS GreatBritain Dec. 18, 1919

